I know this has been covered before, but I will ask again. I want a tranny that is close ratio, not one that drops 1000 rpm with each shift. What are the gear ratios that I am looking for? I like how 1st and 2nd pull, third needs something, maybe a flipped fifth? What does one do about 4th and 5th? What about costs. I ahve been thinking about a six install, but I figure I need to learn how to drive the 4 banger still, so going six would be opening a whole new can o' worms. Enlighten me

There are a lot of variables involved in gearing selection -- engine, track/speed range, and tire size among them.

I went with A,GA,KA (flipped 5th),Q,V (stock 914-4 4th) and the difference in the "kick" when grabbing the upper gears is very noticable. If you leave your F 2nd alone, which is only about 4mph slower @ 7Krpm's, then you only have to buy 1 gear if I have this right.

You have to keep in mind that my car is a six with the redline set at 7200rpm's and almost any shift is occuring beyond a stock 914-4's redline. The torque curve is also very different from a 914-4. So you will want to play around with the "gears" spreadsheets a bit to figure out your shift points and optimal speed-in-gear.

An LSD is also a very worthy addition, esp. if you drive in tight low/medium speed corners a lot, and/or have a decent amount of torque. I went with the Guard 80% unit. It helps stabilize the back end under high speed braking too. (A Quaife/Torsen type will not do that AFAIK.)

Costs largely depend how much stuff you replace in the trans 'while you're in there'. The LSD's are not cheap; gears are actually not very expensive relatively speaking. The sliders, dogteeth, synchros, bearings and all that jazz can add up if you do a complete rebuild as opposed to a quickie freshening.

Another thing,

The optimum tranny would be built around the dyno results...

It depends upon your cams and dyno results as to where you should be shifting as well as redline.

then factor in your tracks, longest straight. The ring and pinion and tire size....

this yields the optimum gear ratios... of course in the real world somethings are not optimum

brant

I currently have several transmissions and none have the right gearing for a 2l six on any sort of long race track. The curernt ratios are K, Q, X for the top three gears which were great for a stroker 4 but too big of a drop for the high revving 6. Most of the VARA and HSR West 2l Porsche cars run M, S, V for the top three gears and that works really well. I guess the bottom line is there is no one gear box that will cover all the tracks and for use with a 4 or a 6. Good luck

ok regarding LSD, has any one looked at the wevco spooler and beside price whats the down side. Basically keeps both rear wheels at the same speed. strictly a racing app. And is there linkinfo on the other lsd other than the quaiffe.

I don't think Paul Guard (GT Transmission) has a web site, but he will send you a nice color glossy info packet if you call or email. gears@gte.net I think. He also advertises in the major p-car mags. Very Nice Parts.

Do searching around.. there is info out there.
The factory "other" limited slip is known as a ZF or clutch pack type LSD.... Its not maintance free, but does have the benefit of allowing you to vary the ratio to the amount you want.

Regarding the spool... again do a search.
That spool is a work of art, and weighs less than a welded diff... but I believe its the same thing. A fully locked diff. Common in dragsters. VERY debateable around here.
I personally like them and use one. I personally picked up 2 seconds with my welded diff, but It took a damn long time to learn how to take advantage of it.

Definately not something for a non trailered car... Boy did it tripple my tire wear.

brant

I really like the flipped 5th gear for 3rd, even for the street. You should try my car when I come back.

Geoff